Cover locking cartons



COVERLOCKING CARTONS Filed Jan; 3, i956 Inventors WILL/AM E BARR/NGTON WILL/AM SKILLEN By=/" I #6 Attys United States Patent COVER LOCKING CARTONS William F. Harrington and William Skillen, London, On-

tario, Canada, assignors to Somerville. Limited, London, Ontario, Canada Application January 3, 1956, Serial No. 557,172

Claims priority, application Canada August 5, 1955 3 Claims. (31. 229-36) This invention relates to cover locking cartons, and more particularly to cartons wherein the cover is releasably locked and adapted for carrying commodities and in particular food products.

The utility of the invention may be illustrated by reference to its use as a food carrier; for instance, when fish is packed in boxes for freezing the compressed product will in the first instance tend to push up a cover that is not secure and consequently the package will cause trouble in the freezing machinery. However, by providing a releasable lock the contents are pressed down and held by the locked cover which will eliminate bulging and consequent difficulty just as jamming in the overwrapping machine. Alternatively, though the cover is firmly locked, it is releasably locked and is readily opened by the housewife by overcoming slight resistance of the cover lock to effect release.

The invention is designed to produce a simple form of box or carton with a minimum of parts projecting beyond the normal confines thereof and which automatically locks when pressed down and readily releases when subjected to slight opening pressure.

The invention generally comprises a cover locking carton embodying four walls and a base forming a carton shell open at the top and a cover hingedly connected to a rear wall thereof, said cover including as well front and end walls adapted to fit over corresponding walls of the carton shell when the cover is closed, said end walls of the cover including a ledge or shoulder located interiorly thereof adjacent the cover, the front wall of said carton wall having a longitudinally hinged flap extending along its length on the upper edge thereof disposed to incline inwardly thereof and partially to overlie the enclosure formed by the carton shell, said flap being of a length greater than the front wall of the carton shell and in effect forming co-extensive tabs projecting slightly beyond the end Walls of said carton shell, said projecting tabs being flexible and adapted to have wiping engagement with the interior surface of said end walls of the cover when the latter is moved to and from closed position, the free ends of said tabs being caused to project over each ledge or shoulder of said end walls of the cover when the latter is closed releasably to lock said cover in closed position on said carton shell.

The invention will be clearly understood by reference to the following detailed specification taken in conjunction with the accompanying drawings.

In the drawings:

Fig. l is a perspective view of a carton according to the present invention showing the cover open; and

Fig. 2 is a fragmentary perspective detail with part of the carton broken away to show the manner in which locking is effected.

Referring to the drawings, A indicates the carton as a whole which is comprised by a carton shell and a cover therefor 11. The carton shell 10 is made up of front and rear walls 12 and 13 and end walls 14 and 15,

2,768,777 Patented Oct. 30, 1956 2v the latter being secured in the form shown by securing tabs 16 hingedly connected to the front and rear walls 12-and 13 and secured to the end walls 14 and 15 in any suitable manner such as by adhesive.

The cover 11 is hingedly connected to the rear wall 13 of the carton shell and is formed with a front wall 17 and end walls 18 and 19, the latter being united to the front wall by means oftabs 20 hingedly connected to the, front wall 17 and secured to, the side walls 18 and 19 by any suitable means such as adhesive. It will be noted that the upper edge of the tabs 20 are spaced from the inside of the cover in effect to form on the interior of the end walls a ledge or shoulder 21.

Along the top edgeof the frontwall 12 of the carton shell a flap 22 is hingedly connected. This flap is of a length greater than the length of the front wall 12 and, therefore, provides at each end of the flap freelyprojecting tabs-23and 24. The flap 22 is normally disposed to project inwardly of the front wall 12 and partially to overlie the enclosure of the carton shell so that the tabs 23 and 24 lie directly above and projectslightly beyond the outer surface of the end walls 14 and 15 of the carton shell. Thus, it will be obvious that when the cover 11 is swung downwardly to close the carton and the end walls 18 and 19 of the cover, along with the front wall 17, are caused to enclose the corresponding walls of the carton shell, the tabs 23 and 24 will have wiping contact with the interior surfaces of the end walls 18 and 19 of the cover, in this closing operation, and in particular with the inner surface of the securing tabs 20 therefor.

Thus, in the process, these tabs 23 and 24 will be caused to fiex slightly downwardly until the carton is closed when the tabs will be in a position to register with the space between the ledge or shoulder 21 of the securing tabs 2% and the inner surface of the cover so that in effect they will snap over the shoulder 21 and lock the cover in its closed position. In particular, it will be noted that the projecting tabs 23 and 24 will be supported partially by the upper edge of the end walls 14 and 15 of the carton shell so that they will have a firm flexing action as a result of this support and, therefore, they move into overlapping engagement with the ledges or shoulders 21 of the tabs 20 automatically when these ledges or shoulders pass the plane of the flap 22 and the co-extensive tabs 23 and 24. Conversely, the tabs 23 and 24 will be caused to flex in the opposite direction when an upward pressure is applied to the cover in an opening operation and the tabs will then release from the shoulders or ledges 21 of the securing tabs 20 to permit opening of the carton.

It will be apparent from the foregoing that a very simple construction is provided which will effect an eificient locking of the cover when closed while also permitting release thereof and which is primarily identified with an inwardly projecting flap having co-extensive outwardly projecting tabs, the free ends of which slightly project beyond the ends of the carton shell. While the ledges or shoulders 21 provided by the securing tabs 20 of the cover form cooperating elements of the lock effected, it will be understood of course that other means might be provided for effecting this securement of the cover and that the structure illustrated is the preferred form of securement.

We claim:

1. A cover locking carton comprising a base having front, rear and end walls forming a carton shell open at the top and a cover hingedly connected to the rear wall thereof, said cover including front and end walls adapted to fit over and enclose the corresponding walls of said carton shell, said front wall of said carton shell having a longitudinally hinged flap extending along the upper edge of the front wall and projecting inwardly thereof partially to overlie the enclosure formed by the carton shell, said flap being of a length greater than the front wall of the carton shell in effect to form co-extensive freely projecting tabs overlying and projecting beyond the end walls of said carton shell, said tabs being adapted for wiping contact with the inner surface of the end walls of said cover, and cooperating locking means incorporated in the end walls of said cover to engage said tabs when said cover is closed to secure said cover in the closed position.

2. A cover locking carton comprising a base having front, rear and end walls forming a carton shell open at the top and a cover hingedly connected to the rear wall thereof, said cover including front and end walls adapted to fit over and enclose the corresponding walls of said carton shell, said end walls of said cover including a ledge interiorly thereof adjacent to and in spaced relation to the cover, said front wall of said carton shell having a longitudinally hinged flap extending along the upper edge of the front wall and projecting inwardly thereof partially to overlie the enclosure formed by the carton shell, said flap being of a length greater than the front wall of the carton shell in effect to form co-extensive freely projecting tabs overlying and projecting beyond the end walls of said carton shell, said tabs being adapted for wiping contact with the inner surface of the end walls of said cover and to project over the adjacent ledge of said end walls of the cover when the latter passes the plane of said tabs thereby to lock and secure said cover in closed position.

3. A carton as claimed in claim 2 in which the end walls of the cover are secured to the front wall of the cover by means of securing tabs, said tabs having an upper edge located in closely spaced relation to the cover and forming said ledges over which the locking tabs project in abutting engagement to efiect the lock and secure the cover in closed position.

References Cited in the file of this patent UNITED STATES PATENTS 

